The manufacture of the latest sandwich structures, such as those used in modern aircraft and motor vehicles, requires various heating processes. An infrared heating system from Heraeus Noblelight offers the flexibility both for experimental series as well as for manufacturing. The Institute for Lightweight Construction and Plastics Technology (ILK) of the Technical University (TU), Dresden has used this to improve new combination processes, such as thermo pressing.
The TU Institute has now transferred these innovative processes that they are now economically viable and will shortly be ready for production.Foam technologies will be increasingly used in future as, combined with new joining technologies, they can improve the properties of many components and pave the way for new applications. Typical requirements in this new technology are the functionality and integration capability of components, while, at the same time, reducing component weight and manufacturing costs.
In thermo pressing, sheets of resin-impregnated composite sheets are joined with foam sheets. To do this, the sandwich made up of thermoplastic composite top and bottom layers and core material, is created in a press tool. Heated semi-finished products are transported into a press tool, together with foam sheets, which are layered at top and bottom with the composite sections. On closing the tool, the covering layers and the foam core are brought together and formed under pressure into a sandwich structure.
Infrared systems transfer heat without the need for a contact medium, with the aid of electro-magnetic waves, which generate the heat directly in the material to be heated. Infrared systems offer very flexible adjustment and control of the output power. At the same time, they feature very short response times, for short wave and carbon emitters, for example, this is a matter of one to three seconds. This means that heating is controllable and allows temperature profiling to be achieved. The flexibility of infrared systems makes them the ideal heat source in the conception phase of new technologies.